This invention relates generally to a process for recycling rubber from tire carcasses and, more particularly, to a process for mass producing rubber paving blocks.
The disposition of used tire carcasses and other similar material has presented a major problem to the tire industry. A number of attempts have been made to recycle the rubber from the tire carcasses, but none have made a significant impact on the growing numbers of used tires that must be disposed each year.
The recycling efforts directed to used tires have devised a process for creating xe2x80x9ccrumb rubberxe2x80x9d from the tire carcasses. Crumb rubber is essentially the rubber portion of the used tires reduced to individual particles that are a xc2xc inch in diameter or smaller. It has been found that this crumb rubber product can be used as a base material to create a number of different products, including paving blocks and other structural products that can provide a surface on which people can walk and vehicles can traverse.
It would be desirable to provide a process by which rubber paving blocks and other similar products can be mass produced in an economically efficient manner. Such a method and the apparatus for practicing the method would enable such products to be available to the public at a cost competitive price with other materials, while significantly decreasing the environmental problems associated with the disposition of used tire carcasses by increasing the recycling thereof.
It is an object of this invention to overcome the disadvantages of the prior art by providing an automated process for manufacturing rubber paving blocks.
It is another object of this invention to provide a method of manufacturing rubber paving blocks that minimizes the utilization of manual labor.
It is an advantage of this invention that tire carcasses will be recycled through the process of manufacturing rubber paving blocks.
It is a feature of this invention that process stations are provided to accomplish the individual steps in manufacturing rubber paving blocks.
It is another feature of this invention that the manufacturing line includes a production line and an oven line interconnected by transfer stations that provide a continuous manufacturing process.
It is another advantage of this invention that the oven line incorporates sufficient time for curing the rubber compound and for the subsequent cooling of the molds before being returned to the production line.
It is still another feature of this invention that pneumatics are incorporated into the manufacturing process.
It is still another object of this invention to provide a method and apparatus for extracting the formed rubber paving block from the mold without damaging the block.
It is yet another object of this invention to provide a lid for the mold which will latch to compress the rubber compound, yet easily release when extraction of the cured rubber paving block is desired.
It is yet another feature of this invention that the lid for the mold includes a latching mechanism that can be actuated by compressed air for both the latching and unlatching functions in the manufacturing process.
It is still another advantage of this invention that the manufacturing process allows for the introduction of a color layer for the exposed surface of the rubber paving block with a less expensive base layer.
It is yet another object of this invention to provide a rubber paving block with a base layer having channels for the passage of water beneath the paving block.
It is yet another feature of this invention that the bottom surface of the rubber paving block is formed with grooves extending radially from a center depressed disk.
It is yet another advantage of this invention that the interconnected grooves and depressed central disk formed into the bottom surface of the formed rubber paving block are operable to provide a passageway for water irrespective of the orientation of the paving block when installed.
It is still another feature of this invention that the central depressed disk in the bottom surface of the formed rubber paving block exerts sufficient tension into the formed block to prevent an upward turning of the rubber material at the exterior corners of the formed block.
It is still another object of this invention to provide a formed rubber paving block with a textured bottom surface and a smooth top surface.
It is a further object of this invention to provide a process that provides a product utilizing crumb rubber made from used tire carcasses, thereby providing an end product for recycling automotive tires.
It is still a further object of this invention to provide an automated process for manufacturing rubber paving blocks from recycled automotive tires which is durable in construction, inexpensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective in use.
It is yet a further object of this invention to provide a formed rubber paving block which is durable in construction, in expensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective in use.
These and other objects, features and advantages are accomplished according to the instant invention in which an automated process for manufacturing rubber paving blocks uses crumb rubber recovered from used automotive tires. The manufacturing process includes a production line in which the molds are emptied of the formed rubber paving block and then filled with a fresh crumb rubber mixture, and a balanced oven line in which the compressed crumb rubber mixture is heated, cured and cooled before being returned to the production line for further processing. The production line includes a station for each individual step in the manufacturing process. The mold includes a lid having latching mechanisms that are actuated by compressed air blasts for both the latching and unlatching functions. The formed rubber paving block is removed from the cooled mold through an extraction mechanism that both engages the textured surface of the formed block and lifts the block through a compressed air apparatus so that the formed block is not damaged during the extraction process. The rubber paving block is formed with a textured bottom surface having a central depressed disk and a plurality of grooves extending radially from the central depressed disk. The textured bottom surface of the formed block provides an interconnected passageway for water to pass beneath the blocks when installed. The central depressed disk also tenses the formed rubber block to restrain the peripheral edges from turning upwardly.